Map INTERVAL types to Python types

Co-authored-by: Damian Owsianny <[email protected]>

Author: hovaesco

tests/integration/test_types_integration.py

@@ -6,6 +6,7 @@
 from zoneinfo import ZoneInfo
 
 import pytest
+from dateutil.relativedelta import relativedelta
 
 import trino
 from tests.integration.conftest import trino_version
@@ -733,14 +734,80 @@ def create_timezone(timezone_str: str) -> tzinfo:
         return ZoneInfo(timezone_str)
 
 
-def test_interval(trino_connection):
-    SqlTest(trino_connection) \
-        .add_field(sql="CAST(null AS INTERVAL YEAR TO MONTH)", python=None) \
-        .add_field(sql="CAST(null AS INTERVAL DAY TO SECOND)", python=None) \
-        .add_field(sql="INTERVAL '3' MONTH", python='0-3') \
-        .add_field(sql="INTERVAL '2' DAY", python='2 00:00:00.000') \
-        .add_field(sql="INTERVAL '-2' DAY", python='-2 00:00:00.000') \
-        .execute()
+def test_interval_year_to_month(trino_connection):
+    (
+        SqlTest(trino_connection)
+        .add_field(
+            sql="CAST(null AS INTERVAL YEAR TO MONTH)",
+            python=None)
+        .add_field(
+            sql="INTERVAL '10' YEAR",
+            python=relativedelta(years=10))
+        .add_field(
+            sql="INTERVAL '-5' YEAR",
+            python=relativedelta(years=-5))
+        .add_field(
+            sql="INTERVAL '3' MONTH",
+            python=relativedelta(months=3))
+        .add_field(
+            sql="INTERVAL '-18' MONTH",
+            python=relativedelta(years=-1, months=-6))
+        .add_field(
+            sql="INTERVAL '30' MONTH",
+            python=relativedelta(years=2, months=6))
+        # max supported INTERVAL in Trino
+        .add_field(
+            sql="INTERVAL '178956970-7' YEAR TO MONTH",
+            python=relativedelta(years=178956970, months=7))
+        # min supported INTERVAL in Trino
+        .add_field(
+            sql="INTERVAL '-178956970-8' YEAR TO MONTH",
+            python=relativedelta(years=-178956970, months=-8))
+    ).execute()
+
+
+def test_interval_day_to_second(trino_connection):
+    (
+        SqlTest(trino_connection)
+        .add_field(
+            sql="CAST(null AS INTERVAL DAY TO SECOND)",
+            python=None)
+        .add_field(
+            sql="INTERVAL '2' DAY",
+            python=timedelta(days=2))
+        .add_field(
+            sql="INTERVAL '-2' DAY",
+            python=timedelta(days=-2))
+        .add_field(
+            sql="INTERVAL '-2' SECOND",
+            python=timedelta(seconds=-2))
+        .add_field(
+            sql="INTERVAL '1 11:11:11.116555' DAY TO SECOND",
+            python=timedelta(days=1, seconds=40271, microseconds=116000))
+        .add_field(
+            sql="INTERVAL '-5 23:59:57.000' DAY TO SECOND",
+            python=timedelta(days=-6, seconds=3))
+        .add_field(
+            sql="INTERVAL '12 10:45' DAY TO MINUTE",
+            python=timedelta(days=12, seconds=38700))
+        .add_field(
+            sql="INTERVAL '45:32.123' MINUTE TO SECOND",
+            python=timedelta(seconds=2732, microseconds=123000))
+        .add_field(
+            sql="INTERVAL '32.123' SECOND",
+            python=timedelta(seconds=32, microseconds=123000))
+        # max supported timedelta in Python
+        .add_field(
+            sql="INTERVAL '999999999 23:59:59.999' DAY TO SECOND",
+            python=timedelta(days=999999999, hours=23, minutes=59, seconds=59, milliseconds=999))
+        # min supported timedelta in Python
+        .add_field(
+            sql="INTERVAL '-999999999' DAY",
+            python=timedelta(days=-999999999))
+    ).execute()
+
+    SqlExpectFailureTest(trino_connection).execute("INTERVAL '1000000000' DAY")
+    SqlExpectFailureTest(trino_connection).execute("INTERVAL '-999999999 00:00:00.001' DAY TO SECOND")
 
 
 def test_array(trino_connection):

trino/mapper.py

@@ -8,6 +8,8 @@
 from typing import Any, Dict, Generic, List, Optional, Tuple, TypeVar
 from zoneinfo import ZoneInfo
 
+from dateutil.relativedelta import relativedelta
+
 import trino.exceptions
 from trino.types import (
     POWERS_OF_TEN,
@@ -167,6 +169,40 @@ def _fraction_to_decimal(fractional_str: str) -> Decimal:
     return Decimal(fractional_str or 0) / POWERS_OF_TEN[len(fractional_str)]
 
 
+class IntervalYearToMonthMapper(ValueMapper[relativedelta]):
+    def map(self, value: Any) -> Optional[relativedelta]:
+        if value is None:
+            return None
+        is_negative = value[0] == "-"
+        years, months = (value[1:] if is_negative else value).split('-')
+        years, months = int(years), int(months)
+        if is_negative:
+            years, months = -years, -months
+        return relativedelta(years=years, months=months)
+
+
+class IntervalDayToSecondMapper(ValueMapper[timedelta]):
+    def map(self, value: Any) -> Optional[timedelta]:
+        if value is None:
+            return None
+        is_negative = value[0] == "-"
+        days, time = (value[1:] if is_negative else value).split(' ')
+        hours, minutes, seconds_milliseconds = time.split(':')
+        seconds, milliseconds = seconds_milliseconds.split('.')
+        days, hours, minutes, seconds, milliseconds = (int(days), int(hours), int(minutes), int(seconds),
+                                                       int(milliseconds))
+        if is_negative:
+            days, hours, minutes, seconds, milliseconds = -days, -hours, -minutes, -seconds, -milliseconds
+        try:
+            return timedelta(days=days, hours=hours, minutes=minutes, seconds=seconds, milliseconds=milliseconds)
+        except OverflowError as e:
+            error_str = (
+                f"Could not convert '{value}' into the associated python type, as the value "
+                "exceeds the maximum or minimum limit."
+            )
+            raise trino.exceptions.TrinoDataError(error_str) from e
+
+
 class ArrayValueMapper(ValueMapper[List[Optional[Any]]]):
     def __init__(self, mapper: ValueMapper[Any]):
         self.mapper = mapper
@@ -271,6 +307,10 @@ def _create_value_mapper(self, column: Dict[str, Any]) -> ValueMapper[Any]:
             return TimestampValueMapper(self._get_precision(column))
         if col_type == 'timestamp with time zone':
             return TimestampWithTimeZoneValueMapper(self._get_precision(column))
+        if col_type == 'interval year to month':
+            return IntervalYearToMonthMapper()
+        if col_type == 'interval day to second':
+            return IntervalDayToSecondMapper()
 
         # structural types
         if col_type == 'array':